title: Predictors of peritonitis, hospital days, and technique survival for peritoneal dialysis patients in a managed care setting.
abstract: BACKGROUND
  Many clinicians perceive that peritoneal dialysis (PD) should be reserved for younger, healthier, more affluent patients. Our aim was to examine outcomes for PD patients in a managed care setting and to identify predictors of adverse outcomes.
  
  
  METHODS
  We identified all patients who initiated PD at our institution between 1 January 2001 and 31 December 2010. Predictor variables studied included age, sex, race, PD modality, cause of end-stage renal disease (ESRD), dialysis vintage, Charlson comorbidity index (CCI) score, education, and income level. Poisson models were used to determine the relative risk (RR) of peritonitis and the number of hospital days per patient-year. The log-rank test was used to compare technique survival by patient strata.
  
  
  RESULTS
  Among the 1378 patients who met the inclusion criteria, only female sex [RR: 0.85; 95% confidence interval (CI): 0.74 to 0.98; p = 0.02] and higher education (RR: 0.77; 95% CI: 0.60 to 0.98; p = 0.04) were associated with peritonitis. For hospital days, dialysis vintage (RR: 1.11; 95% CI: 1.04 to 1.18; p = 0.002), CCI score (RR: 1.06; 95% CI: 1.02 to 1.20; p = 0.002), and cause of ESRD (RR for glomerulonephritis: 0.59; 95% CI: 0.43 to 0.80; p = 0.0006; and RR for hypertension: 0.69; 95% CI: 0.55 to 0.88; p = 0.002) were associated with 1 extra hospital day per patient-year. The 2-year technique survival was 61% for patients who experienced at least 1 episode of peritonitis and 72% for those experiencing no peritonitis (p = 0.0001). Baseline patient age, primary cause of ESRD, and PD modality were the only other variables associated with technique survival in the study.
  
  
  CONCLUSIONS
  Neither race nor socio-economic status predicted technique survival or hospital days in our study. Female sex and higher education were the only two variables studied that had an association with peritonitis.
authors.affiliation: Department of Internal Medicine,1 Division of Nephrology, Southern California Permanente Medical Group, Los Angeles, and Research and Evaluation,2 Southern California Permanente Medical Group, Pasadena, California, USA.
authors.forename: Victoria A
authors.initials: VA
authors.lastname: Kumar
authors.forename: Margo A
authors.initials: MA
authors.lastname: Sidell
authors.forename: Wan-Ting
authors.initials: WT
authors.lastname: Yang
authors.forename: Jason P
authors.initials: JP
authors.lastname: Jones
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000628:therapy; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008329:Managed Care Programs; D008875:Middle Aged; D010530:Peritoneal Dialysis; D010538:Peritonitis / Q000175:diagnosis* / Q000453:epidemiology*; D011446:Prospective Studies; D012307:Risk Factors; D016019:Survival Analysis
keywords: CAPD; PD outcome; hospital days; peritonitis; socio-economic status; technique survival